The Nathpa Jhakri hydroelectric scheme is located on the Satluj River in Himachal Pradesh Province, India, about 400 kilometres north-west of Delhi.
This run-of-river scheme develops a net head of 425 metres and has a total installed capacity of 1500 MW. The headworks consist of a concrete gravity dam, power intake structures and four large underground desilting chambers. The headrace tunnel is 27 kilometres-long, and its design discharge is 405 m³/s. The 21 metre diameter and 300 metre deep surge chamber is one of the deepest in the world. The three inclined pressure shafts feed the six Francis turbines in the underground power house. The 980 metre long tailrace tunnel returns the turbine discharge to the river.
Nathpa Jhakri, one of the largest hydropower schemes in India, produces 7450 GWh in an average hydrological year.
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